Generally, a fuel injection device is configured by combining plural cylindrical valve bodies in which a high-pressure fuel channel is formed therein. The fuel channel formed in each valve body is open at an end surface of each valve body in an axial direction. An axial force is applied to the plural valve bodies by using a fastening member, such that the end surfaces of the plural valve bodies opened in an axial direction liquid-tightly contact each other.
Even in this case, the high-pressure fuel in the fuel channel of the fuel injection device may be easily leaked from a space between the end surfaces of the valve bodies. In a fuel injection device described in Patent Document 1 (WO 00/60233), one of the end surfaces of the adjacent valve bodies has an end surface groove recessed from the end surface. Furthermore, a recovery channel for recovering leakage fuel leaked from the fuel channel is formed in the valve body. The recovery channel is connected to the end surface groove, so that the leakage fuel leaked to the end surface groove can be recovered via the recovery channel.
In the fuel injection device described in Patent Document 1, the contact area between the end surfaces of the adjacent valve bodies adjacent to each other in the axial direction can be reduced by the end surface groove.
However, recently, the pressure of the fuel supplied to the fuel injection device is increased more and more. When an abnormity is caused in a supply portion for supplying a high-pressure fuel to the fuel injection device, the pressure of the fuel in the fuel channel may be increased remarkably.
In the fuel injection device described in Patent Document 1, when an axial force is applied to the valve bodies so as to liquid-tightly contact the end surfaces of the valve bodies, the surface pressure caused between the end surface portions at an inner peripheral side of the end surface groove is substantially equal to the surface pressure caused between the end surface portions at an outer peripheral side of the end surface groove. In this case, the axial force applied to the end surfaces of the valve bodies is distributed in the end surface portions, and the surface pressure may be insufficient for liquid-tightly contacting the end surface portions at the inner peripheral side of the end surface groove. If the fuel is continuously leaked from the fuel channel to the end surface groove, the recovery of the leakage fuel via the recovery channel connected to the end surface groove may be insufficient. Thus, if the fuel pressure in the end surface groove is increased, the fuel may be leaked from the end surface groove to the outside of the fuel injection device. Therefore, it may be difficult to prevent a fuel leakage to an outside of the fuel injection device in Patent Document 1.